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如图,已知⊙O的半径OA=6,∠AOB=90°,则∠AOB所对的弧AB的长为( ...
如图,已知⊙O的半径OA=6,∠AOB=90°,则∠AOB所对的弧AB的长为( )
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103102446931193624/SYS201311031024469311936009_ST/images0.png)
A.2π
B.3π
C.6π
D.12π
考点分析:
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